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Measurement of the H and tH production rates in the H decay channel using proton-proton collision data at = 13 TeV
No full textInternational audienceAn analysis of the production of a Higgs boson (H) in association with a top quark-antiquark pair (H) or a single top quark (tH) is presented. The Higgs boson decay into a bottom quark-antiquark pair (H ) is targeted, and three different final states of the top quark decays are considered, defined by the number of leptons (electrons or muons) in the event. The analysis utilises proton-proton collision data collected at the CERN LHC with the CMS experiment at = 13 TeV in 2016-2018, which correspond to an integrated luminosity of 138 fb. The observed H production rate relative to the standard model expectation is 0.33 0.26 = 0.33 0.17 (stat) 0.21 (syst). Additionally, the H production rate is determined in intervals of Higgs boson transverse momentum. An upper limit at 95% confidence level is set on the tH production rate of 14.6 times the standard model prediction, with an expectation of 19.3. Finally, constraints are derived on the strength and structure of the coupling between the Higgs boson and the top quark from simultaneous extraction of the H and tH production rates, and the results are combined with those obtained in other Higgs boson decay channels
Optimal Control for Linear Systems with -norm Cost
No full textInternational audienceWe study -optimal stabilization of linear systems with finite and infinite horizons. Main results concern the existence, uniqueness and structure of optimal solutions, and the robustness of optimal cost
Distributional Reduction: Unifying Dimensionality Reduction and Clustering with Gromov-Wasserstein
No full textInternational audienceUnsupervised learning aims to capture the underlying structure of potentially large and high-dimensional datasets. Traditionally, this involves using dimensionality reduction (DR) methods to project data onto lower-dimensional spaces or organizing points into meaningful clusters (clustering). In this work, we revisit these approaches under the lens of optimal transport and exhibit relationships with the Gromov-Wasserstein problem. This unveils a new general framework, called distributional reduction, that recovers DR and clustering as special cases and allows addressing them jointly within a single optimization problem. We empirically demonstrate its relevance to the identification of low-dimensional prototypes representing data at different scales, across multiple image and genomic datasets
Conway's cosmological theorem and automata theory
No full textInternational audienceJohn Conway proved that every audioactive sequence (a.k.a. \emph{look-and-say}) decays into a compound of 94~elements, a statement he termed the \emph{cosmological theorem}. The underlying audioactive process can be modeled by a finite-state machine, mapping one sequence of integers to another. Leveraging automata theory, we propose a new proof of Conway's theorem based on a few simple machines, using a computer to compose and minimize them
Curvature in chemotaxis: A model for ant trail pattern formation
No full textInternational audienceIn this paper, we propose a new model of chemotaxis motivated by ant trail pattern formation, formulated as a coupled parabolic-parabolic local PDE system, for the population density and the chemical field. The main novelty lies in the transport term of the population density, which depends on the second-order derivatives of the chemical field. This term is derived as an anticipation-reaction steering mechanism of an infinitesimally small ant as its size approaches zero. We establish global-in-time existence and uniqueness for the model, and the propagation of regularity from the initial data. Then, we build a numerical scheme and present various examples that provide hints of trail formation
Open-Canopy: Towards Very High Resolution Forest Monitoring
No full text22 pages, 8 figures, Submitted to NeurIPS 2024 Datasets and Benchmarks TrackInternational audienceEstimating canopy height and its changes at meter resolution from satellite imagery remains a challenging computer vision task with critical environmental applications. However, the lack of open-access datasets at this resolution hinders the reproducibility and evaluation of models. We introduce Open-Canopy, the first open-access, country-scale benchmark for very high-resolution (1.5 m) canopy height estimation, covering over 87,000 km² across France with 1.5 m panchromatic resolution satellite imagery and aerial LiDAR data. Additionally, we present Open-Canopy-, a benchmark for canopy height reduction detection between images from different years at tree level---a difficult task for current computer vision models. We evaluate state-of-the-art architectures on these benchmarks, highlighting significant challenges and opportunities for improvement. Our datasets and code are publicly available at \url{https://github.com/fajwel/Open-Canopy}
Search for light long-lived particles decaying to displaced jets in proton-proton collisions at = 13.6 TeV
No full textInternational audienceA search for light long-lived particles decaying to displaced jets is presented, using a data sample of proton-proton collisions at a center-of-mass energy of 13.6 TeV, corresponding to an integrated luminosity of 34.7 fb, collected with the CMS detector at the CERN LHC in 2022. Novel trigger, reconstruction, and machine-learning techniques were developed for and employed in this search. After all selections, the observations are consistent with the background predictions. Limits are presented on the branching fraction of the Higgs boson to long-lived particles that subsequently decay to quark pairs or tau lepton pairs. An improvement by up to a factor of 10 is achieved over previous limits for models with long-lived particle masses smaller than 60 GeV and proper decay lengths smaller than 1 m. The first constraints are placed on the fraternal twin Higgs and folded supersymmetry models, where the lower bounds on the top quark partner mass reach up to 350 GeV for the fraternal twin Higgs model and 250 GeV for the folded supersymmetry model
Measurement of inclusive and differential cross sections of single top quark production in association with a W boson in proton-proton collisions at = 13.6 TeV
No full textInternational audienceThe first measurement of the inclusive and normalised differential cross sections of single top quark production in association with a W boson in proton-proton collisions at a centre-of-mass energy of 13.6 TeV is presented. The data were recorded with the CMS detector at the LHC in 2022, and correspond to an integrated luminosity of 34.7 fb. The analysed events contain one muon and one electron in the final state. For the inclusive measurement, multivariate discriminants exploiting the kinematic properties of the events are used to separate the signal from the dominant top quark-antiquark production background. A cross section of 82.3 2.1 (stat) (syst) 3.3 (lumi) pb is obtained, consistent with the predictions of the standard model. A fiducial region is defined according to the detector acceptance to perform the differential measurements. The resulting differential distributions are unfolded to particle level and show good agreement with the predictions at next-to-leading order in perturbative quantum chromodynamics
First determination of the spin-parity of baryons
No full textInternational audienceThe decay chains are observed, and the spin-parity of baryons is determined for the first time. The measurement is performed using proton-proton collision data at a center-of-mass energy of , corresponding to an integrated luminosity of , recorded by the~ experiment between 2016 and 2018. The spin-parity of the baryons is determined to be with a significance of more than () compared to all other tested hypotheses. The up-down asymmetries of the transitions are measured to be (), consistent with maximal parity violation, where the first uncertainty is statistical and the second is systematic. These results support the hypothesis that the baryons correspond to the first -wave -mode excitation of the flavor triplet
Measurement of inclusive jet cross section and substructure in collisions at GeV
No full textInternational audienceThe jet cross-section and jet-substructure observables in collisions at GeV were measured by the PHENIX Collaboration at the Relativistic Heavy Ion Collider (RHIC). Jets are reconstructed from charged-particle tracks and electromagnetic-calorimeter clusters using the anti- algorithm with a jet radius for jets with transverse momentum within GeV/ and pseudorapidity . Measurements include the jet cross section, as well as distributions of SoftDrop-groomed momentum fraction (), charged-particle transverse momentum with respect to jet axis (), and radial distributions of charged particles within jets (). Also meaureed was the distribution of , where is the fraction of the jet momentum carried by the charged particle. The measurements are compared to theoretical next-to and next-to-next-to-leading-order calculatios, PYTHIA event generator, and to other existing experimental results. Indicated from these meaurements is a lower particle multiplicity in jets at RHIC energies when compared to models. Also noted are implications for future jet measurements with sPHENIX at RHIC as well as at the future Election-Ion Collider